Tumor Necrosis Factor (TNF) is a master pro-inflammatory cytokine that coordinates tissue homeostasis by regulating cytokine production, cell survival and cell death. TNF-induced cell death originates from the cytosolic Complex II that forms upon TNFR1 activation. By eliminating infected cells, cell death can be a beneficial response in the context of infection. However, when induced aberrantly or in excess, TNF-induced cell death can also promote an uncontrolled amplifying loop of inflammation that drives disease development. Therefore, cell demise is not the standard outcome of TNF sensing because several protective brakes or cell death checkpoints prevent the cytosolic accumulation of the cytotoxic Complex II. This research project aims at characterizing a new cell death checkpoint in the TNF pathway, consisting in the detoxification of the TNFR1 cytosolic death-inducing Complex II by endosomal micro-autophagy (eMI) – a still poorly characterized form of autophagy. In addition to promoting lysosomal degradation, eMI also mediates the extracellular release of cargo as part of exosomes, a type of extracellular vesicles that have emerged as crucial players in intercellular communication. The project proposal aims at further characterizing the process of eMI and at studying its role in regulating TNF signaling, using both cell death and intercellular communication as readouts. To reach this goal, we will integrate experiments at the biochemical, cellular and organismal level.